Age- and menopause-associated variations in body composition and fat distribution in healthy women as measured by dual-energy X-ray absorptiometry

Sex differences in risk factors for vascular contributions to cognitive impairment & dementia

Vascular contributions to cognitive impairment and dementia (VCID) is the second most common cause of dementia. While males overall appear to be at a slightly higher risk for VCID throughout most of the lifespan (up to age 85), some risk factors for VCID more adversely affect women. These include female-specific risk factors associated with pregnancy related disorders (e.g. preeclampsia), menopause, and poorly timed hormone replacement. Further, presence of certain co-morbid risk factors, such as diabetes, obesity and hypertension, also may more adversely affect women than men. In contrast, some risk factors more greatly affect men, such as hyperlipidemia, myocardial infarction, and heart disease. Further, stroke, one of the leading risk factors for VCID, has a higher incidence in men than in women throughout much of the lifespan, though this trend is reversed at advanced ages. This review will highlight the need to take biological sex and common co-morbidities for VCID into account in both preclinical and clinical research. Given that there are currently no treatments available for VCID, it is critical that we understand how to mitigate risk factors for this devastating disease in both sexes.

Sex differences in metabolism and cardiometabolic disorders

PURPOSE OF REVIEW

Sex differences are pervasive in metabolic and cardiovascular traits, yet they have often been ignored in human and animal model research. Sex differences can arise from reversible hormonal effects, from irreversible organizational (developmental) processes, and from gene expression differences from the X and Y chromosomes. We briefly review our current understanding of the impact of these factors in metabolic traits and disorders, with an emphasis on the recent literature.

RECENT FINDINGS

Novel sex differences continue to be identified for metabolic and cardiovascular traits. For example, it is now clear that gut microbiota tend to differ between men and women, with potentially large implications for disease susceptibility. Also, tissue-specific gene regulation differs between men and women, contributing to differential metabolism. These new insights will open up personalized therapeutic avenues for cardiometabolic diseases.

SUMMARY

Sex differences in body fat distribution, glucose homeostasis, insulin signaling, ectopic fat accumulation, and lipid metabolism during normal growth and in response to hormonal or nutritional imbalance are mediated partly through sex hormones and the sex chromosome complement. Most of these differences are mediated in a tissue-specific manner. Important future goals are to better understand the interactions between genetic variation and sex differences, and to bring an understanding of sex differences into clinical practice.

Sex differences in lipid and lipoprotein metabolism

BACKGROUND

Endogenous sex hormones are important for metabolic health in men and women. Before menopause, women are protected from atherosclerotic cardiovascular disease (ASCVD) relative to men. Women have fewer cardiovascular complications of obesity compared to men with obesity. Endogenous estrogens have been proposed as a mechanism that lessens ASCVD risk, as risk of glucose and lipid abnormalities increases when endogenous estrogens decline with menopause. While baseline risk is higher in males than females, endogenously produced androgens are also protective against fatty liver, diabetes and ASCVD, as risk goes up with androgen deprivation and with the decline in androgens with age.

SCOPE OF REVIEW

In this review, we discuss evidence of how endogenous sex hormones and hormone treatment approaches impact fatty acid, triglyceride, and cholesterol metabolism to influence metabolic and cardiovascular risk. We also discuss potential reasons for why treatment strategies with estrogens and androgens in older individuals fail to fully recapitulate the effects of endogenous sex hormones.

MAJOR CONCLUSIONS

The pathways that confer ASCVD protection for women are of potential therapeutic relevance. Despite protection relative to men, ASCVD is still the major cause of mortality in women. Additionally, diabetic women have similar ASCVD risk as diabetic men, suggesting that the presence of diabetes may offset the protective cardiovascular effects of being female through unknown mechanisms.

High Body Mass Index Masks Body Composition Differences in Physically Active Versus Sedentary Participants

BACKGROUND

Despite the benefits of aerobic exercise on body composition, runners with high body mass index (BMI) remain understudied. We examined body composition differences between sedentary insulin-resistant [obese insulin-resistant sedentary (OS-IR)], sedentary insulin-sensitive [obese insulin-sensitive sedentary (OS-IS)], and trained [obese trained (OT)] individuals with high BMI (≥25 kg/m²). We hypothesized that after matching for high BMI, OT individuals would have less fat mass (absolute and relative) and greater lean mass than OS-IR or OS-IS individuals.

METHODS

This is a retrospective analysis of OS-IR, OS-IS, and OT participants selected for similar age, sex, and BMI. Activity was self-reported. OT participants exercised at least 30 min/day (predominantly running) for 3-5 days/week. OS-IS and OS-IR participants actively exercised <0.5 hr/week. Body composition was measured by dual X-ray absorptiometry.

RESULTS

Thirty-three participants were recruited [n = 11/group, mean age 31.7 years (standard error): (0.9)], 7 females/group, overall BMI [31.6 kg/m² (0.7)]. Insulin resistance, quantified by the homeostatic model assessment for insulin resistance, was higher in the OS-IR [3.3 (0.2)] than the OS-IS [0.9 (0.2): P < 0.0001] or OT [1.6 (0.2): P < 0.0001] groups. We found the following: (i) Compared to the OS-IR group, the OT group had lower region-specific fat mass as measured by percent fat (trunk) or absolute fat mass (trunk, android region, and abdominal visceral region). (ii) OT and OS-IS groups had similar body composition. (iii) Total fat mass and percent body fat correlated with BMI, (iv) Visceral fat correlated with BMI (r = 0.80, P = 0.003) only in the OS-IR (P = 0.03 for BMI × group interaction).

CONCLUSIONS

Using BMI to classify obesity masks body composition differences in high BMI individuals discrepant for insulin resistance and physical activity status.

Body composition, cardiometabolic risk factors, physical activity, and inflammatory markers in premenopausal women after a 10-year follow-up: a MONET study

OBJECTIVE

Menopausal transition and postmenopause are usually associated with changes in body composition and a decrease in physical activity energy expenditure (PAEE). This study investigated body composition, cardiometabolic risk factors, PAEE, and inflammatory markers in premenopausal women after a 10-year follow-up.

METHODS

In all, 102 premenopausal women participated in the 5-year observational longitudinal Montreal Ottawa New Emerging Team (MONET) study. This present substudy included 48 participants (age: 60.0 ± 1.7 years; body mass index: 23.2 ± 2.2 kg/m) 6.0 ± 0.3 years after completion of the initial MONET study. Measures included body composition, waist circumference (WC), fasting glucose and insulin levels, insulin sensitivity (QUICKI model), plasma lipid levels, PAEE, and inflammatory markers.

RESULTS

Compared with baseline measures of the MONET study, analyses revealed no significant increase in body weight, although there were significant increases in WC, fat mass (FM), % FM, total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol, haptoglobin, apolipoprotein B, ferritin, adiponectin, and soluble cluster of differentiation 14 (all P < 0.001) after the 10-year follow-up. However, significant decreases were observed for fat-free mass, PAEE, fasting glucose levels, interleukin-8 levels, and soluble tumor necrosis factor receptors 1 and 2 (sTNFR-1 and sTNFR-2) levels (all P < 0.05). To determine the effect of postmenopausal years, data were restructured based on final menstrual period (FMP), and one-way analyses of variance were performed.Waist circumference, % FM, total cholesterol, high-density lipoprotein cholesterol, apolipoprotein B, ferritin, adiponectin, and soluble cluster of differentiation 14 were higher in early and late postmenopausal periods in these women. sTNFR-1 and sTNFR-2 levels were higher at the FMP and early postmenopausal years as compared with the late postmenopausal periods. Finally, interleukin-8 levels were lower in years after FMP.

CONCLUSION

The number of years elapsed since the FMP can affect body composition, cardiometabolic risk factors, and inflammatory markers in healthy premenopausal women going through menopausal transition and postmenopausal periods.

Effects of ovariectomy and exercise training intensity on energy substrate and hepatic lipid metabolism, and spontaneous physical activity in mice

BACKGROUND

Menopause is associated with fatty liver, glucose dysregulation, increased body fat, and impaired bone quality. Previously, it was demonstrated that single sessions of high-intensity interval exercise (HIIE) are more effective than distance- and duration-matched continuous exercise (CE) on altering hepatic triglyceride (TG) metabolism and very-low density lipoprotein-TG (VLDL-TG) secretion.

METHODS

Six weeks training using these modalities was examined for effects on hepatic TG metabolism/secretion, glucose tolerance, body composition, and bone mineral density (BMD) in ovariectomized (OVX) and sham-operated (SHAM) mice. OVX and SHAM were assigned to distance- and duration-matched CE and HIIE, or sedentary control.

RESULTS

Energy expenditure during exercise was confirmed to be identical between CE and HIIE and both similarly reduced post-exercise absolute carbohydrate oxidation and spontaneous physical activity (SPA). OVX vs. SHAM displayed impaired glucose tolerance and greater body fat despite lower hepatic TG, and these outcomes were not affected by training. Only HIIE increased hepatic AMPK in OVX and SHAM, but neither training type impacted VLDL-TG secretion. As expected, BMD was lower in OVX, and training did not affect long bones.

CONCLUSIONS

The results reveal intensity-dependent effects on hepatic AMPK expression and general exercise effects on subsequent SPA and substrate oxidation that is independent of estrogen status. These findings support the notion that HIIE can impact aspects of liver physiology in females while the effects of exercise on whole body substrate selection appear to be independent of training intensity. However, neither exercise approach mitigated the impairment in glucose tolerance and elevated body fat occurring in OVX mice.

Prevalence of General and Central Obesity and Associated Factors among North Korean Refugees in South Korea by Duration after Defection from North Korea: A Cross-Sectional Study

Previous studies on obesity status among North Korean refugees (NKRs) have been limited. We investigated mean body mass index (BMI), waist circumference (WC), and general and central obesity prevalence among NKRs in South Korea (SK) by duration after defection from North Korea (NK), using cross-sectional data of the North Korean Refugee Health in South Korea (NORNS) study and compared these data with a sample from the general South Korean population (the fifth Korea National Health and Nutrition Examination Survey). The prevalence of general and central obesity among NKRs with duration after defection from NK of less than five years were lower than among South Koreans, except for central obesity among NKR females (obesity prevalence, 19% (12⁻27%) vs. 39% (34⁻44%) for NK vs. SK males (p < 0.001) and 19% (14⁻24%) vs. 27% (24⁻29%) for NK vs. SK females (p = 0.076); central obesity prevalence, 13% (6⁻19%) vs. 24% (20⁻29%) for NK vs. SK males (p = 0.011) and 22% (17⁻28%) vs. 20% (18⁻22%) for NK vs. SK females (p = 0.382)). The prevalence of general and central obesity among NKRs with duration after defection from NK (≥10 years) were comparable to those of South Koreans in both genders (obesity prevalence, 34% (18⁻50%) vs. 39% (34⁻44%) for NK vs. SK males (p = 0.690) and 23% (18⁻29%) vs. 27% (24⁻29%) for NK vs. SK females (0.794); central obesity prevalence, 21% (7⁻34%) vs. 24% (20⁻29%) for NK vs. SK males (p = 0.642); 22% (17⁻28%) vs. 20% (18⁻22%) for NK vs. SK females (p = 0.382)). Male sex, age and longer duration after defection from NK (≥10 years) were positively associated with obesity. As for central obesity, age was the only independently associated factor. NKR females with duration after defection from NK of less than five years had comparable central obesity prevalence to South Korean females in spite of a lower BMI, which suggests that we need further monitoring for their metabolic health among NKRs in SK.

Secular Trends in Energy and Macronutrient Intakes and Distribution among Adult Females (1991-2015): Results from the China Health and Nutrition Survey

With rapid nutrition transition in China, dietary intake and nutritional status of women has gained more and more attention in the past decades. This study aimed to investigate temporal trends of total energy and macronutrient intakes among Chinese adult females. The longitudinal data are from the Chinese Health and Nutrition Survey (CHNS, 1991-2015). Information on the intake of energy and macronutrient was obtained from consecutive three-day dietary recall techniques and compared with the Chinese Dietary Reference Intakes (DRI). Mixed-effect models were performed to evaluate temporal trends of total energy and macronutrient intake. From 1991 to 2015, a significant reduction in daily energy, protein and carbohydrate intakes was seen among all adult females (p < 0.001). Daily fat intake, the proportion of energy from fat, the proportion of females consuming more than 30% of energy from fat and less than 50% of energy from carbohydrate were observed significant increment in the present study (p < 0.001). In 2015, the proportion met the DRI for energy and protein intakes were 47.0% and 48.0%, respectively; the proportion with lower carbohydrate and higher fat intakes compare with the DRI were 45.5% and 66.9%, respectively. Further nutritional education and policy interventions still needed to improve nutrition status for Chinese females.

Elucidating the role of plexin D1 in body fat distribution and susceptibility to metabolic disease using a zebrafish model system

Non-communicable diseases (NCDs) such as cardiovascular disease, diabetes and cancer were responsible for 68% of all deaths worldwide in 2012. The regional distribution of lipid deposited within adipose tissue (AT) - so called body fat distribution (BFD) - is a strong risk factor for NCDs. BFD is highly heritable; however, the genetic basis of BFD is almost entirely unknown. Genome-wide association studies have identified several loci associated with BFD, including at Plexin D1 (PLXND1) - a gene known to modulate angiogenesis. We recently demonstrated that zebrafish homozygous for a null mutation in plxnd1 had a reduced capacity to store lipid in visceral AT (VAT) leading to altered BFD. Moreover, we found that type V collagens were upregulated in plxnd1 mutants, and mediated the inhibitory effect of Plxnd1 on VAT growth. These results strengthen evidence that Plxnd1 influences BFD in human populations, and validate zebrafish as a model to study BFD. However, many pertinent questions remain unanswered. Here we outline potential Plxnd1 mechanisms of action in AT, and describe the genetic architecture at human PLXND1 that is associated with BFD and NCD susceptibility.

Ovarian hormones and obesity

BACKGROUND

Obesity is caused by an imbalance between energy intake, i.e. eating and energy expenditure (EE). Severe obesity is more prevalent in women than men worldwide, and obesity pathophysiology and the resultant obesity-related disease risks differ in women and men. The underlying mechanisms are largely unknown. Pre-clinical and clinical research indicate that ovarian hormones may play a major role.

OBJECTIVE AND RATIONALE

We systematically reviewed the clinical and pre-clinical literature on the effects of ovarian hormones on the physiology of adipose tissue (AT) and the regulation of AT mass by energy intake and EE.

SEARCH METHODS

Articles in English indexed in PubMed through January 2016 were searched using keywords related to: (i) reproductive hormones, (ii) weight regulation and (iii) central nervous system. We sought to identify emerging research foci with clinical translational potential rather than to provide a comprehensive review.

OUTCOMES

We find that estrogens play a leading role in the causes and consequences of female obesity. With respect to adiposity, estrogens synergize with AT genes to increase gluteofemoral subcutaneous AT mass and decrease central AT mass in reproductive-age women, which leads to protective cardiometabolic effects. Loss of estrogens after menopause, independent of aging, increases total AT mass and decreases lean body mass, so that there is little net effect on body weight. Menopause also partially reverses women's protective AT distribution. These effects can be counteracted by estrogen treatment. With respect to eating, increasing estrogen levels progressively decrease eating during the follicular and peri-ovulatory phases of the menstrual cycle. Progestin levels are associated with eating during the luteal phase, but there does not appear to be a causal relationship. Progestins may increase binge eating and eating stimulated by negative emotional states during the luteal phase. Pre-clinical research indicates that one mechanism for the pre-ovulatory decrease in eating is a central action of estrogens to increase the satiating potency of the gastrointestinal hormone cholecystokinin. Another mechanism involves a decrease in the preference for sweet foods during the follicular phase. Genetic defects in brain α-melanocycte-stimulating hormone-melanocortin receptor (melanocortin 4 receptor, MC4R) signaling lead to a syndrome of overeating and obesity that is particularly pronounced in women and in female animals. The syndrome appears around puberty in mice with genetic deletions of MC4R, suggesting a role of ovarian hormones. Emerging functional brain-imaging data indicates that fluctuations in ovarian hormones affect eating by influencing striatal dopaminergic processing of flavor hedonics and lateral prefrontal cortex processing of cognitive inhibitory controls of eating. There is a dearth of research on the neuroendocrine control of eating after menopause. There is also comparatively little research on the effects of ovarian hormones on EE, although changes in ovarian hormone levels during the menstrual cycle do affect resting EE.

WIDER IMPLICATIONS

The markedly greater obesity burden in women makes understanding the diverse effects of ovarian hormones on eating, EE and body adiposity urgent research challenges. A variety of research modalities can be used to investigate these effects in women, and most of the mechanisms reviewed are accessible in animal models. Therefore, human and translational research on the roles of ovarian hormones in women's obesity and its causes should be intensified to gain further mechanistic insights that may ultimately be translated into novel anti-obesity therapies and thereby improve women's health.

Development of a Whole-Body Physiologically Based Pharmacokinetic Approach to Assess the Pharmacokinetics of Drugs in Elderly Individuals

Background

Because of the vulnerability and frailty of elderly adults, clinical drug development has traditionally been biased towards young and middle-aged adults. Recent efforts have begun to incorporate data from paediatric investigations. Nevertheless, the elderly often remain underrepresented in clinical trials, even though persons aged 65 years and older receive the majority of drug prescriptions. Consequently, a knowledge gap exists with regard to pharmacokinetic (PK) and pharmacodynamic (PD) responses in elderly subjects, leaving the safety and efficacy of medicines for this population unclear.

Objectives

The goal of this study was to extend a physiologically based pharmacokinetic (PBPK) model for adults to encompass the full course of healthy aging through to the age of 100 years, to support dose selection and improve pharmacotherapy for the elderly age group.

Methods

For parameterization of the PBPK model for healthy aging individuals, the literature was scanned for anthropometric and physiological data, which were consolidated and incorporated into the PBPK software PK-Sim^®. Age-related changes that occur from 65 to 100 years of age were the main focus of this work. For a sound and continuous description of an aging human, data on anatomical and physiological changes ranging from early adulthood to old age were included. The capability of the PBPK approach to predict distribution and elimination of drugs was verified using the test compounds morphine and furosemide, administered intravenously. Both are cleared by a single elimination pathway. PK parameters for the two compounds in younger adults and elderly individuals were obtained from the literature. Matching virtual populations—with regard to age, sex, anthropometric measures and dosage—were generated. Profiles of plasma drug concentrations over time, volume of distribution at steady state (V_ss) values and elimination half-life (t_½) values from the literature were compared with those predicted by PBPK simulations for both younger adults and the elderly.

Results

For most organs, the age-dependent information gathered in the extensive literature analysis was dense. In contrast, with respect to blood flow, the literature study produced only sparse data for several tissues, and in these cases, linear regression was required to capture the entire elderly age range. On the basis of age-informed physiology, the predicted PK profiles described age-associated trends well. The root mean squared prediction error for the prediction of plasma concentrations of furosemide and morphine in the elderly were improved by 32 and 49 %, respectively, by use of age-informed physiology. The majority of the individual V_ss and t_½ values for the two model compounds, furosemide and morphine, were well predicted in the elderly population, except for long furosemide half-lifes.

Conclusion

The results of this study support the feasibility of using a knowledge-driven PBPK aging model that includes the elderly to predict PK alterations throughout the entire course of aging, and thus to optimize drug therapy in elderly individuals. These results indicate that pharmacotherapy and safety-related control of geriatric drug therapy regimens may be greatly facilitated by the information gained from PBPK predictions.

Electronic supplementary material

The online version of this article (doi:10.1007/s40262-016-0422-3) contains supplementary material, which is available to authorized users.

Menopausal Hormone Therapy and Type 2 Diabetes Prevention: Evidence, Mechanisms, and Clinical Implications

Type 2 diabetes has reached epidemic proportions in the United States. Large, randomized controlled trials suggest that menopausal hormone therapy (MHT) delays the onset of type 2 diabetes in women. However, the mechanisms and clinical implications of this association are still a matter of controversy. This review provides an up-to-date analysis and integration of epidemiological, clinical, and basic studies, and proposes a mechanistic explanation for the effect of menopause and MHT on type 2 diabetes development and prevention. We discuss the beneficial effects of endogenous estradiol with respect to insulin secretion, insulin sensitivity, and glucose effectiveness; we also discuss energy expenditure and adipose distribution, both of which are affected by menopause and improved by MHT, which thereby decreases the incidence of type 2 diabetes. We reconcile differences among studies that investigated the effect of menopause and MHT formulations on type 2 diabetes. We argue that discrepancies arise from physiological differences in methods used to assess glucose homeostasis, ranging from clinical indices of insulin sensitivity to steady-state methods to assess insulin action. We also discuss the influence of the route of estrogen administration and the addition of progestogens. We conclude that, although MHT is neither approved nor appropriate for the prevention of type 2 diabetes due to its complex balance of risks and benefits, it should not be withheld from women with increased risk of type 2 diabetes who seek treatment for menopausal symptoms.

Polycyclic aromatic hydrocarbons and postmenopausal breast cancer: An evaluation of effect measure modification by body mass index and weight change

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs) have been linked to breast cancer in many, but not all, previous studies. PAHs are lipophilic and stored in fat tissue, which we hypothesized may result in constant low-dose exposure to these carcinogens. No previous studies have evaluated whether obesity modifies associations between multiple measures of PAHs and breast cancer incidence.

METHODS

This population-based study included 1,006 postmenopausal women with first primary in situ or invasive breast cancer and 990 age-frequency matched controls. To evaluate effect modification by obesity (adult body mass index (BMI, kg/m²) and weight change) on multiple PAH measures (the biomarker PAH-DNA adducts, and long-term sources active cigarette smoking, living with a smoking spouse, grilled/smoked meat intake, residential synthetic log burning, and vehicular traffic), interaction contrast ratios (ICRs) for the additive scale, and ratio of odds ratios (RORs) with log-likelihood ratio tests (LRT) for the multiplicative scale, were determined using unconditional logistic regression.

RESULTS

BMI modified the PAH-DNA adduct and postmenopausal breast cancer association on the additive (ICR: 0.49; 95% CI: 0.01, 0.96) and multiplicative (ROR: 1.56; 95% CI: 0.91, 2.68) scales. The odds ratio for detectable vs. non-detectable adducts was increased among women with BMI ≥25 (OR=1.34; 95% CI: 0.94, 1.92), but not in those with BMI <25 (OR=0.86; 95% CI: 0.57, 1.28) (LRT p=0.1). For most other PAH measures, the pattern of modification by BMI/weight gain was similar, but estimates were imprecise.

CONCLUSIONS

The association between PAH-DNA adducts and breast cancer incidence may be elevated among overweight/obese women.

Role of Estrogens in the Regulation of Liver Lipid Metabolism

Before menopause, women are protected from atherosclerotic heart disease associated with obesity relative to men. Sex hormones have been proposed as a mechanism that differentiates this risk. In this review, we discuss the literature around how the endogenous sex hormones and hormone treatment approaches after menopause regulate fatty acid, triglyceride, and cholesterol metabolism to influence cardiovascular risk.The important regulatory functions of estrogen signaling pathways with regard to lipid metabolism have been in part obscured by clinical trials with hormone treatment of women after menopause, due to different formulations, routes of delivery, and pairings with progestins. Oral hormone treatment with several estrogen preparations increases VLDL triglyceride production. Progestins oppose this effect by stimulating VLDL clearance in both humans and animals. Transdermal estradiol preparations do not increase VLDL production or serum triglycerides.Many aspects of sex differences in atherosclerotic heart disease risk are influenced by the distributed actions of estrogens in the muscle, adipose, and liver. In humans, 17β-estradiol (E2) is the predominant circulating estrogen and signals through estrogen receptor alpha (ERα), estrogen receptor beta (ERβ), and G-protein-coupled estrogen receptor (GPER). Over 1000 human liver genes display a sex bias in their expression, and the top biological pathways are in lipid metabolism and genes related to cardiovascular disease. Many of these genes display variation depending on estrus cycling in the mouse. Future directions will likely rely on targeting estrogens to specific tissues or specific aspects of the signaling pathways in order to recapitulate the protective physiology of premenopause therapeutically after menopause.

Interleukins 6 and 8 and abdominal fat depots are distinct correlates of lipid moieties in healthy pre- and postmenopausal women

Available data associate lipids concentrations in men with body mass index, anabolic steroids, age, and certain cytokines. Data were less clear in women, especially across the full adult lifespan, and when segmented by premenopausal and postmenopausal status.

SUBJECTS

120 healthy women (60 premenopausal and 60 postmenopausal) in Olmsted County, MN, USA, a stable well studied clinical population. Dependent variables: measurements of 10 h fasting high-density lipoprotein cholesterol, total cholesterol, low-density lipoprotein cholesterol, and triglycerides.

INDEPENDENT VARIABLES

testosterone, estrone, estradiol, 5-alpha-dihydrotestosterone, and sex-hormone binding globulin (by mass spectrometry); insulin, glucose, and albumin; abdominal visceral, subcutaneous, and total abdominal fat [abdominal visceral fat, subcutaneous fat, total abdominal fat by computerized tomography scan]; and a panel of cytokines (by enzyme-linked immunosorbent assay). Multivariate forward-selection linear-regression analysis was applied constrained to P < 0.01. Lifetime data: High-density lipoprotein cholesterol was correlated jointly with age (P < 0.0001, positively), abdominal visceral fat (P < 0.0001, negatively), and interleukin-6 (0.0063, negatively), together explaining 28.1 % of its variance (P = 2.3 × 10^-8). Total cholesterol was associated positively with multivariate age only (P = 6.9 × 10^-4, 9.3 % of variance). Triglycerides correlated weakly with sex-hormone binding globulin (P = 0.0115), and strongly with abdominal visceral fat (P < 0.0001), and interleukin-6 (P = 0.0016) all positively (P = 1.6 × 10^-12, 38.9 % of variance). Non high-density lipoprotein cholesterol and low-density lipoprotein cholesterol correlated positively with both total abdominal fat and interleukin-8 (P = 2.0 × 10^-5, 16.9 % of variance; and P = 0.0031, 9.4 % of variance, respectively). Premenopausal vs. postmenopausal comparisons identified specific relationships that were stronger in premenopausal than postmenopausal individuals, and vice versa. Age was a stronger correlate of low-density lipoprotein cholesterol; interleukin-6 of triglycerides and high-density lipoprotein; and both sex-hormone binding globulin and total abdominal fat of non high-density lipoprotein cholesterol in premenopausal than postmenopausal women. Conversely, sex-hormone binding globulin, abdominal visceral fat, interleukin-8, adiponectin were stronger correlates of triglycerides; abdominal visceral fat, and testosterone of high-density lipoprotein cholesterol; and age of both non high-density lipoprotein and low-density lipoprotein in postmenopausal than premenopausal women. Our data delineate correlations of total abdominal fat and interleukin-8 (both positively) with non high-density lipoprotein cholesterol and low-density lipoprotein cholesterol in healthy women across the full age range of 21-79 years along with even more specific associations in premenopausal and postmenopausal individuals. Whether some of these outcomes reflect causal relationships would require longitudinal and interventional or genetic studies.

Association of Mid-Life Changes in Body Size, Body Composition and Obesity Status with the Menopausal Transition

The mid-life period is a critical window for increases in body weight and changes in body composition. In this review, we summarize the clinical experience of the menopausal transition by obesity status, and examine the evidence regarding the menopausal transition and reproductive hormones effects on body weight, body composition, or fat distribution. Mid-life obesity is associated with a different menopausal experience including associations with menstrual cycle length prior to the final menstrual period (FMP), age at the FMP, and higher prevalence of vasomotor symptoms. The menopausal transition is associated with weight gain and increased central body fat distribution; the majority of evidence suggests that changes in weight are due to chronological aging whereas changes in body composition and fat distribution are primarily due to ovarian aging. Continuous and regular physical activity during mid-life may be an efficacious strategy to counteract the age-related and menopause-related changes in resting energy expenditure and to prevent weight gain and abdominal adiposity deposition.

High pulse pressure is related to risk of type 2 diabetes mellitus in Chinese middle-aged females

BACKGROUND

To examine the association of risk of incident type 2 diabetes mellitus (T2DM) with high pulse pressure (PP) by sex.

METHODS

We performed a prospective cohort study of 12,272 eligible participants (4664 males and 7608 females) without diabetes at baseline. Participants were classified as having normal PP (20-60mmHg) and high PP (>60mmHg) at baseline. The analysis was further stratified by sex, quartiles of age and high PP categories.

RESULTS

During 6years of follow-up, T2DM developed in 775 participants and the incidence was 10.57/1000person-years. With PP 70 to 76mmHg, the multivariable adjusted hazard ratio (HR) (95% confidence interval) for incident T2DM in females was 1.722 (1.093-2.714) after adjustment for baseline age, smoking, alcohol intake, physical activity level and family history of T2DM, and 1.634 (1.037-2.575) after adjustment for the above factors and body mass index, waist circumference, blood lipid levels and fasting plasma glucose (FPG) category. After stratification by quartiles of age, for females aged 52 to 59, the multivariable adjusted HRs (95% CI) for high PP as compared to normal PP were 2.263 (1.517-3.377) and 2.140 (1.426-3.210) in different models. During follow-up, levels of FPG, fasting plasma insulin and homeostatic model assessment of insulin resistance index (HOMA-IR) were higher in females with higher than normal PP group, but β-cell function was impaired in the high PP group (P<0.05).

CONCLUSION

High PP may be related to incident T2DM among female in China, especially women 52 to 59years old.

Effect of menopausal hormone therapy on components of the metabolic syndrome

The world population is aging, and women will spend an increasing share of their lives in a postmenopausal state that predisposes to metabolic dysfunction. Thus, the prevalence of metabolic syndrome (MetS) in women is likely to increase dramatically. This article summarizes the effects of menopause in predisposing to components of MetS including visceral obesity, dyslipidemia, type 2 diabetes (T2D) and hypertension (HTN). We also summarize the effects of menopausal hormone therapy (MHT) in reversing these metabolic alterations and discuss therapeutic advances of novel menopausal treatment on metabolic function.

Body composition in the Study of Women Entering and in Endocrine Transition (SWEET): A perspective of African women who have a high prevalence of obesity and HIV infection

OBJECTIVES

Little data are available for sub-Saharan African women on changes in body composition in menopause transition (MT). The study aimed to determine whether there are differences in body adiposity, lean muscle mass, and bone mineral density (BMD) across MT groups in urban African women, who have a high prevalence of obesity and HIV infection, and if this is related to an altered hormonal milieu.

DESIGN

Participants were 702 black urban women. Menopause stage was defined using STRAW+10 criteria. Levels of follicle stimulating hormone (FSH), estradiol (E2), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), testosterone (T) and sex hormone blinding globulin (SHBG) were measured. Body composition was measured with dual-energy X-ray absorptiometry (DXA) and ultrasound scans.

RESULTS

Whole body lean mass (p=0.002) and BMD (p<0.0005) were significantly lower in postmenopausal compared to premenopausal groups. Estradiol (p<0.0005), SHBG (p<0.0005) and DHEAS (p=0007) were significantly lower in post- than premenopausal groups, while FSH was higher (p<0.0005). FSH correlated negatively (β=-2.06, p<0.0005) with total lean mass while E2 correlated positively (β=20.0, p=0.002) with BMD. Use of antiretroviral therapy (ART) correlated negatively with total fat mass (β=-2.92, p=0.008) and total bone mineral content (BMC; β=-78.8, p=0.003).

CONCLUSIONS

The MT in this population is characterized by lower whole body lean mass and BMD in post- compared to premenopausal subjects but there are minimal differences in fat mass. Lower lean mass and BMD were associated with higher FSH and lower E2 serum levels, respectively. Use of ART was associated with lower fat mass and BMC.

Sarcopenia and body composition in diabetic Charcot osteoarthropathy

BACKGROUND

Treatment of Charcot osteoarthropathy (COA) requires restricted walking and offloading for several months, which lead to fat re-distribution and increased sarcopenia.

OBJECTIVES/AIM

To investigate whether subjects with COA have an altered body composition compared to controls.

METHODS

Cross-sectional case-control study of people with diabetes with acute or chronic Charcot osteoarthropathy, matched with otherwise healthy people with diabetes. A total of 49 subjects (distribution ~1:1) had a total body DXA-scanning, measuring appendicular lean mass, android/gynoid and truncal/total body fat distribution ratios.

RESULTS

Sarcopenia frequency was higher in the total population with diabetes overall (9-40%), compared to normal materials. Using two different models for correlating appendicular lean mass to sarcopenia, there were no differences in sarcopenia-rates between the groups (P=0.413 and 0.948 respectively). There was no significant difference in lean tissue mass between the affected and the unaffected leg in the immobilised subject group (P=0.830). The average fat percentage was (29.4-37.7%) in the population with diabetes, compared to a matching background population (24.5-31.9%), whereas there were no significant differences found between the groups (P=0.065). Neither truncal/total fat percent nor android/gynoid fat percent ratios showed differences between the groups.

CONCLUSION

To our knowledge, this is the first published dataset investigating body composition in subjects with Charcot osteoarthropathy. The study population of diabetics were more fat and sarcopenic than normal subjects, whereas no statistically significant impact of Charcot osteoarthropathy was found.

Accuracy of segmental bioelectrical impedance analysis for predicting body composition in pre- and postmenopausal women

This study aimed to compare the accuracy for predicting body composition using single-frequent segmental bioelectrical impedance analysis (BIA) between pre- and postmenopausal women. A total f 559 Japanese women aged 30-88yr were divided into 4 groups by questionnaire: natural menopause, pathological menopause, regular menstruation, or irregular menstruation. The measurement values by dual-energy X-ray absorptiometry were used as a reference of the body composition. In terms of the results, regardless of the menopausal status, BIA slightly but significantly overestimated the percentage of body fat (standard error of estimate: 5.3%-6.7%) and the leg lean soft tissue mass (LSTM; 5.1%-6.1%), and underestimated the LSTM in the whole body (6.2%-7.6%) and arm (2.8%-3.7%). The absolute values of the predictive error for leg LSTM were significantly higher in postmenopausal groups than in the premenopausal ones. The corresponding values for the whole body and arm LSTM, and the percentage of body fat were higher in premenopausal groups than in postmenopausal ones. In conclusion, the predictive accuracy of BIA for postmenopausal women is not inferior to that for premenopausal ones, unless we target the leg LSTM.

Body Image in Adult Women: Moving Beyond the Younger Years

In spite of copious literature investigating body dissatisfaction and its correlates in adolescents and young adult women, exploration of body image disturbances in adult women remains an underrepresented domain in the literature. Yet, there are many reasons to suspect that body image in adult women both may differ from and possibly be more complex than that of younger women. Adult women face myriad factors influencing body image beyond those delineated in the body image literature on adolescents and young adult women. For instance, aging-related physiological changes shift the female body further away from the thin-young-ideal, which is the societal standard of female beauty. Further, life priorities and psychological factors evolve with age as well. As such, adult women encounter changes that may differentially affect body image across the lifespan. This paper aims to provide an up-to-date review of the current literature on the relationship between body image and associated mental and physical health problems and behaviors in adult women. In addition, we explore factors that may influence body image in adult women. Lastly, we use this review to identify significant gaps in the existing literature with the aim of identifying critical targets for future research.

Influência dos hormônios sexuais no consumo de oxigênio de ratos

Introdução: Achados da literatura sugerem que oscilações dos hormônios sexuais femininos podem alterar o consumo máximo de oxigênio (VO2max).Objetivo: Comparar o VO2max entre ratos machos (M, n=8), fêmeas nas fases ovulatórias (OV, n=8) ou não-ovulatórias (NOV, n=8) do ciclo estral e ooforectomizadas (OS, n=8).Métodos: A avaliação do consumo de oxigênio foi realizada em esteira rolante com caixa metabólica acoplada.Resultados: Em repouso, o VO2 foi semelhante entre os grupos estudados. O grupo M apresentou maior VO2max em relação ao grupo NOV, mas valores semelhantes ao do grupo OV. O VO2max foi menor no grupo ooforectomizado (OS: 62±3 ml.kg-1.min-1) quando comparado aos demais grupos (M: 92±2; NOV: 77±4; OV: 87±3 ml.kg-1.min-1).Conclusões: Esses achados evidenciam que a variação hormonal decorrente das diferentes fases do ciclo estral e da privação dos hormônios ovarianos pode induzir alterações no consumo máximo de oxigênio em ratos.

In vitro palmitate treatment of myotubes from postmenopausal women leads to ceramide accumulation, inflammation and affected insulin signaling

Menopause is associated with an increased incidence of insulin resistance and metabolic diseases. In a chronic palmitate treatment model, we investigated the role of skeletal muscle fatty acid exposure in relation to the metabolic deterioration observed with menopause. Human skeletal muscle satellite cells were isolated from premenopausal (n = 6) and postmenopausal (n = 5) women. In an in vitro model, the myotubes were treated with palmitate (300 µM) for one-, two- or three days during differentiation. Effects on lipid accumulation, inflammation and insulin signaling were studied. Palmitate treatment led to a 108% (CI 95%: 50%; 267%) increase in intramyocellular ceramide in the myotubes from the postmenopausal women (post-myotubes) compared with a 26% (CI 95%: -57%; 96%) increase in myotubes from the premenopausal women (pre-myotubes), (p<0.05). Furthermore, post-myotubes had a 22% (CI 95%: 4%; 34%) increase in pJNK (p = 0.04) and a 114% (CI 95%: 50%; 177%) increase in Hsp70 protein expression (p = 0.03) after three days of palmitate treatment, compared with pre-myotubes, in which no increase in either pJNK (-12% (CI 95: -26%; 2%)) or Hsp70 (7% (CI 95: -78%; 91%)) was detected. Furthermore, post-myotubes showed a blunted insulin stimulated phosphorylation of AS160 in response to chronic palmitate treatment compared with pre-myotubes (p = 0.02). The increased intramyocellular ceramide content in the post-myotubes was associated with a significantly higher mRNA expression of Serine Palmitoyltransferase1 (SPT1) after one day of palmitate treatment (p = 0.03) in post-myotubes compared with pre-myotubes. Our findings indicate that post-myotubes are more prone to develop lipid accumulation and defective insulin signaling following chronic saturated fatty acid exposure as compared to pre-myotubes.

Associations of physical activity and inactivity with body tissue composition among healthy Polish women and women after mastectomy

The aim of the study is to determine the relationship between physical activity and body composition among healthy women and women who have had mastectomy. This is in order to establish whether physical activity of women after breast cancer treatment improves composition and distribution of body mass components to a degree which will allow to achieve the body composition of healthy women. Research material consists of anthropometric measurements (body height, weight) of women and bioelectric impedance analysis (BIA) of body composition (using Akern - BIA 101 composition analyzer). Intensity of activity was assessed using the Physical Activity International Questionnaire. The sample consisted of 76 healthy women (active 44.74%, inactive 55.26%) and 70 females after mastectomy (54.29% and 45.71%, respectively). Mean chronological age of women after mastectomy was 53.40 years, SD=7.55, and of the healthy ones 52.38 years SD=11.01). A significant difference in body composition was noted among active and inactive women after mastectomy; namely the active females had lower weight (by approximately 12 kg), body mass index (BMI), level of fat mass (by approximately 8%) and (by approximately 5%) total body water. The active healthy women had 6% less fat mass, almost 4% more body water and 6% more fat free mass. Programmed physical activity undertaken by women after mastectomy is recommended and produces good results in the form of reduction of excessive body fat tissue. Through physical activity these women are able to achieve the same level of fat mass as healthy women.

Age-related differences in abdominal fat distribution in premenopausal and postmenopausal women with cardiovascular disease

OBJECTIVE

The aim of this study was to determine the effect of sex and the menopausal transition on age-related differences in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) among patients with cardiovascular disease.

METHODS

A cross-sectional study of 997 women and 3,409 men with cardiovascular disease was performed. VAT and SAT were measured by ultrasonography. Differences in abdominal fat per decade in premenopausal and postmenopausal women were analyzed with linear regression and compared with men younger and older than the mean menopause age of women.

RESULTS

VAT increased gradually across advancing age groups. For postmenopausal women, the 10-year differences in VAT were smaller than those for premenopausal women (0.24 cm [β = 0.24; 95% CI, 0.05 to 0.43] vs 0.71 cm [β = 0.71; 95% CI, 0.29 to 1.12]). There were no differences in SAT (β = -0.12; 95% CI, -0.37 to 0.13) in premenopausal women, and SAT decreased across the age groups of postmenopausal women (-0.36 cm per decade [β = -0.36; 95% CI, -0.47 to -0.26]). Postmenopausal women showed 10-year differences in VAT that were larger than those for men 48 years or older (0.24 cm per decade [β = 0.24; 95% CI, 0.05 to 0.43] vs -0.01 cm per decade [β = -0.01; 95% CI, -0.12 to 0.10]). In addition, 10-year differences in SAT were larger in postmenopausal women than in men 48 years or older (-0.36 cm [β = -0.36; 95% CI, -0.47 to -0.26] vs -0.22 cm [β = -0.22; 95% CI, -0.27 to -0.18]).

CONCLUSIONS

Menopause is not associated with accelerated fat gain in women with cardiovascular disease. Compared with similar-aged men, postmenopausal women show a steeper increase in VAT and a steeper decrease in SAT. These ongoing changes might add to an unfavorable metabolic profile associated with an increased risk of recurrent cardiovascular events.

Aldehyde dehydrogenase 1A1: friend or foe to female metabolism?

In this review, we summarize recent advances in understanding vitamin A-dependent regulation of sex-specific differences in metabolic diseases, inflammation, and certain cancers. We focus on the characterization of the aldehyde dehydrogenase-1 family of enzymes (ALDH1A1, ALDH1A2, ALDH1A3) that catalyze conversion of retinaldehyde to retinoic acid. Additionally, we propose a “horizontal transfer of signaling” from estrogen to retinoids through the action of ALDH1A1. Although estrogen does not directly influence expression of Aldh1a1, it has the ability to suppress Aldh1a2 and Aldh1a3, thereby establishing a female-specific mechanism for retinoic acid generation in target tissues. ALDH1A1 regulates adipogenesis, abdominal fat formation, glucose tolerance, and suppression of thermogenesis in adipocytes; in B cells, ALDH1A1 plays a protective role by inducing oncogene suppressors Rara and Pparg. Considering the conflicting responses of Aldh1a1 in a multitude of physiological processes, only tissue-specific regulation of Aldh1a1 can result in therapeutic effects. We have shown through successful implantation of tissue-specific Aldh1a1^−/− preadipocytes that thermogenesis can be induced in wild-type adipose tissues to resolve diet-induced visceral obesity in females. We will briefly discuss the emerging role of ALDH1A1 in multiple myeloma, the regulation of reproduction, and immune responses, and conclude by discussing the role of ALDH1A1 in future therapeutic applications.

Waist circumference and insulin resistance in elderly men: an analysis of Kahrizak elderly study

Background

Diagnosis of the metabolic syndrome (MS) is crucial for health care practitioners to identify at risk people for early treatment. Visceral obesity may make unnecessary other laborious measures of insulin resistance. The aim of this study was to see whether waist circumference (WC) can predict insulin resistance as well as MS in a group of Iranian elderly.

Methods

Out of 94 nondiabetic elderly, thirty three subjects were recognized with MS. MS diagnosis was based on NCEP ATP III (National Cholesterol Education Program Adult Treatment Panel III) and IDF (International Diabetes Federation) definitions. HOMA (Homeostasis Model Assessment) index was used to measure insulin sensitivity. Insulin resistance (IR) was defined as top quartile of HOMA.

Results

In both sexes, WC and HOMA index were significantly positively correlated. The optimal waist circumference (OWC) cutoff point was 94.5 cm for men and 90.5 cm for women. The high sensitivity (0.80) and specificity (0.84) of WC in males indicates the proportion of IR which is correctly identified and recognizes all non-IR males as such. In regression model only the TG level was associated with WC. But the WC is strongly associated with HOMA-IR.

Conclusions

While OWC is very likely a good measure to exclude non-IR subjects in our study, determination of optimal WC to identify elderly IR subjects warrants further study in a larger sample of the general population.

Expression of inflammation-related genes in gluteal and abdominal subcutaneous adipose tissue during weight-reducing dietary intervention in obese women

Accumulation of adipose tissue in lower body lowers risk of cardiovascular and metabolic disorders. The molecular basis of this protective effect of gluteofemoral depot is not clear. The aim of this study was to compare the profile of expression of inflammation-related genes in subcutaneous gluteal (sGAT) and abdominal (sAAT) adipose tissue at baseline and in response to multiphase weight-reducing dietary intervention (DI). 14 premenopausal healthy obese women underwent a 6 months' DI consisting of 1 month very-low-calorie-diet (VLCD), subsequent 2 months' low-calorie-diet and 3 months' weight maintenance diet (WM). Paired samples of sGAT and sAAT were obtained before and at the end of VLCD and WM periods. mRNA expression of 17 genes (macrophage markers, cytokines) was measured using RT-qPCR on chip-platform. At baseline, there were no differences in gene expression of macrophage markers and cytokines between sGAT and sAAT. The dynamic changes induced by DI were similar in both depots for all genes except for three cytokines (IL6, IL10, CCL2) that differed in their response during weight maintenance phase. The results show that, in obese women, there are no major differences between sGAT and sAAT in expression of inflammation-related genes at baseline conditions and in response to the weight-reducing DI.

Menopause, complement, and hemostatic markers in women at midlife: the Study of Women's Health Across the Nation

OBJECTIVE

To evaluate whether higher circulating levels of complement proteins C3 and C4 are associated with menopausal status and with hemostatic/thrombus formation markers (circulating factor VII (factor VIIc), fibrinogen, plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator antigen (tPA-ag)) in a sample of midlife women.

METHODS AND RESULTS

A total of 100 women (50 late peri-/postmenopausal and 50 pre-/early peri- menopausal women) from the Study of Women's Health Across the Nation (SWAN) Pittsburgh site were included in the present analysis. Factor VIIc and PAI-1 were log transformed. Linear regression was used for analysis. The mean age of the study participants was 50.5 ± 2.6 years with 73% were Caucasian and 27% were African American. C3 but not C4 was significantly higher in postmenopausal women compared to premenopausal women (P value = 0.03), adjusting for age, race and BMI. In final model (adjusting for age, race, BMI and menopausal status), C3 was associated with higher levels of log PAI-1 (P value = 0.0009) and tPA-ag (P value = 0.0003), while C4 was associated with higher levels of log factor VIIc (P value = 0.04) and fibrinogen (P value = 0.005).

CONCLUSIONS

These data suggest that C3 and C4 may be related to blood clots via their associations with hemostatic markers and that C3 is related to menopausal status. Complement proteins C3 and C4 could be possible pathways by which postmenopausal women are at higher risk of atherosclerosis and cardiovascular related events. It is important to replicate these findings in a larger sample size.

Sixteen weeks of resistance training can decrease the risk of metabolic syndrome in healthy postmenopausal women

BACKGROUND

The postmenopausal phase has been considered an aggravating factor for developing metabolic syndrome. Notwithstanding, no studies have as yet investigated the effects of resistance training on metabolic syndrome in postmenopausal women. Thus, the purpose of this study was to verify whether resistance training could reduce the risk of metabolic syndrome in postmenopausal women.

METHODS

Twenty postmenopausal women were randomly assigned to a resistance training protocol (n = 10, 53.40 ± 3.95 years, 64.58 ± 9.22 kg) or a control group (n = 10, 53.0 ± 5.7 years, 64.03 ± 5.03 kg). In the resistance training protocol, ten exercises were performed, with 3 × 8-10 maximal repetitions three times per week, and the load was increased every week. Two-way analysis of variance was used to evaluate specific metabolic syndrome Z-score, high density lipoprotein cholesterol, fasting blood glucose, triglycerides, waist circumference, blood pressure, strength, and body composition. The level of statistical significance was set at P < 0.05.

RESULTS

The main results demonstrated a significant decrease of metabolic syndrome Z-score when the postmenopausal women performed resistance training (P = 0.0162). Moreover, we observed decreases in fasting blood glucose for the resistance training group (P = 0.001), and also significant improvements in lean body mass (P = 0.042, 2.46%), reduction of body fat percentage (P = 0.001, -6.75%) and noticeable increases in muscle strength after resistance training to leg press (P = 0.004, 41.29%) and bench press (P = 0.0001, 27.23%).

CONCLUSION

It was concluded that resistance training performed three times a week may reduce the metabolic syndrome Z-score with concomitant decreases in fasting blood glucose, improvements in body composition, and muscle strength in postmenopausal women.

Sex differences in the physiology of eating

Hypothalamic-pituitary-gonadal (HPG) axis function fundamentally affects the physiology of eating. We review sex differences in the physiological and pathophysiological controls of amounts eaten in rats, mice, monkeys, and humans. These controls result from interactions among genetic effects, organizational effects of reproductive hormones (i.e., permanent early developmental effects), and activational effects of these hormones (i.e., effects dependent on hormone levels). Male-female sex differences in the physiology of eating involve both organizational and activational effects of androgens and estrogens. An activational effect of estrogens decreases eating 1) during the periovulatory period of the ovarian cycle in rats, mice, monkeys, and women and 2) tonically between puberty and reproductive senescence or ovariectomy in rats and monkeys, sometimes in mice, and possibly in women. Estrogens acting on estrogen receptor-α (ERα) in the caudal medial nucleus of the solitary tract appear to mediate these effects in rats. Androgens, prolactin, and other reproductive hormones also affect eating in rats. Sex differences in eating are mediated by alterations in orosensory capacity and hedonics, gastric mechanoreception, ghrelin, CCK, glucagon-like peptide-1 (GLP-1), glucagon, insulin, amylin, apolipoprotein A-IV, fatty-acid oxidation, and leptin. The control of eating by central neurochemical signaling via serotonin, MSH, neuropeptide Y, Agouti-related peptide (AgRP), melanin-concentrating hormone, and dopamine is modulated by HPG function. Finally, sex differences in the physiology of eating may contribute to human obesity, anorexia nervosa, and binge eating. The variety and physiological importance of what has been learned so far warrant intensifying basic, translational, and clinical research on sex differences in eating.

Breast size, thoracic kyphosis & thoracic spine pain - association & relevance of bra fitting in post-menopausal women: a correlational study

BACKGROUND

Menopause would seem to exist as a period of accelerated changes for women and their upper torso mechanics. Whether these anthropometric changes reflect changes in pain states remains unclear. Plausible mechanisms of pain exist for the independent and combined effect of increasing breast size and thoracic kyphosis. Bra fit has the potential to change when the anthropometric measures (chest circumference and bust circumference) used to determine bra size change, such as postmenopausally.Identifying an association between breast size, thoracic kyphosis and thoracic spine pain in postmenopausal women and identifying the relevance of bra fit to this association may be of importance to the future management and education of post-menopausal women presenting clinically with thoracic spine pain.

METHODS

A cross-sectional study design. Fifty-one postmenopausal bra-wearing women were recruited. Measures included breast size (Triumph International), thoracic kyphosis (flexible curve), bra fitted (Y/N) and pain (Short Form McGill Pain Questionnaire) and tenderness on palpation (posteroanterior pressure testing). These measures were collected in one session at a physiotherapy clinic.

RESULTS

The majority of the women in this study were overweight or obese and wearing an incorrect sized bra. Pain was significantly related to breast size, body weight and BMI at mid thoracic levels (T7-8). In contrast self-reported thoracic pain was not correlated with age or index of kyphosis (thoracic kyphosis). Women with thoracic pain were no more likely to have their bra professionally fitted whereas women with a higher BMI and larger breasts were more likely to have their bra professionally fitted.

CONCLUSION

The findings of this study show that larger breasts and increased BMI are associated with thoracic pain in postmenopausal women. This is unrelated to thoracic kyphosis. Increasing breast size and how a bra is worn may have biomechanical implications for the loaded thoracic spine and surrounding musculature. Post-menopause women present with a spectrum of anthropometrical changes that have the potential to contribute to altered biomechanics and affect pain states in the thoracic spine.

Menopause is associated with decreased whole body fat oxidation during exercise

The purpose of this study was to examine if fat oxidation was affected by menopausal status and to investigate if this could be related to the oxidative capacity of skeletal muscle. Forty-one healthy women were enrolled in this cross-sectional study [premenopausal (n = 19), perimenopausal (n = 8), and postmenopausal (n = 14)]. Estimated insulin sensitivity was obtained from an oral glucose tolerance test. Body composition was measured by dual-energy X-ray absorptiometry and magnetic resonance imaging. Fat oxidation and energy expenditure were measured during an acute exercise bout of 45 min of ergometer biking at 50% of maximal oxygen consumption (Vo2 max). Muscle biopsies from the vastus lateralis of the quadriceps muscle were obtained before and immediately after the exercise bout. Postmenopausal women had 33% [confidence interval (CI) 95%: 12-55] lower whole body fat oxidation (P = 0.005) and 19% (CI 95%: 9-22) lower energy expenditure (P = 0.02) during exercise, as well as 4.28 kg lower lean body mass (LBM) than premenopausal women. Correction for LBM reduced differences in fat oxidation to 23% (P = 0.05), whereas differences in energy expenditure disappeared (P = 0.22). No differences between groups were found in mRNA [carnitine palmitoyltransferase I, β-hydroxyacyl-CoA dehydrogenase (β-HAD), peroxisome proliferator-activated receptor-α, citrate synthase (CS), pyruvate dehydrogenase kinase 4, peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α)], protein [phosphorylated AMP-activated protein kinase (AMPK), vascular endothelial growth factor, pyruvate dehydrogenase-1Eα, cytochrome oxidase I], or enzyme activities (β-HAD, CS) in resting skeletal muscle, except for an increased protein level of cytochrome c in the post- and perimenopausal women relative to premenopausal women. Postmenopausal women demonstrated a trend to a blunted exercise-induced increase in phosphorylation of AMPK compared with premenopausal women (P = 0.06). We conclude that reduced whole body fat oxidation after menopause is associated with reduced LBM.

Sex dimorphism and depot differences in adipose tissue function

Obesity, characterized by excessive adiposity, is a risk factor for many metabolic pathologies, such as type 2 diabetes mellitus (T2DM). Numerous studies have shown that adipose tissue distribution may be a greater predictor of metabolic health. Upper-body fat (visceral and subcutaneous abdominal) is commonly associated with the unfavorable complications of obesity, while lower-body fat (gluteal-femoral) may be protective. Current research investigations are focused on analyzing the metabolic properties of adipose tissue, in order to better understand the mechanisms that regulate fat distribution in both men and women. This review will highlight the adipose tissue depot- and sex-dependent differences in white adipose tissue function, including adipogenesis, adipose tissue developmental patterning, the storage and release of fatty acids, and secretory function. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease.

The relationship between endogenous androgens and body fat distribution in early and late postmenopausal women

Objectives

To investigate the relationship between endogenous androgens and body fat distribution in early and late postmenopausal women.

Materials and Methods

We enrolled postmenopausal women consisting of an early group (≤5 years since menopause, n = 105) and a late group (≥10 years since menopause, n = 107). Each group was subdivided into normal weight (BMI <24 kg/m²) group, overweight and obese (BMI ≥24 kg/m²) group. Fasting total testosterone (T), dehydroepiandrosterone-sulfate (DHEA-S) and sex hormone-binding globulin (SHBG) levels were measured. Body fat distribution was evaluated by dual-energy X-ray absorptiometry (DEXA).

Results

Late postmenopausal women had a higher proportion of body fat than early postmenopausal women. The body fat of the overweight and obese women had a greater tendency to accumulate in the abdomen compared with the normal weight women both in early and late postmenopausal groups. The overweight and obese women had a higher free testosterone (FT) than the normal weight women in early postmenopausal women (P<0.05). In late postmenopausal women, the overweight and obese women had higher DHEA-S levels than normal weight women (P<0.05). No direct relationship was observed between the T levels and body fat distribution both in early and late postmenopausal groups (P>0.05).The FT in early postmenopausal women and the DHEA-S levels in late postmenopausal women correlated positively with the trunk/leg fat ratio (T/L) and the proportion of android fat whereas correlated negatively with the proportion of gynoid fat in the partial correlation and multiple linear regression analyses (all P<0.05).

Conclusions

Serum T levels do not correlate directly with body fat distribution, the FT in early postmenopausal women and DHEA-S levels in late postmenopausal women correlate positively with abdominal fat accumulation.

Physical activity and cardiovascular risk factors at menopause: the Nord-Trøndelag health study

BACKGROUND

Lowered physical activity levels may partially explain changes in metabolic risk factors in women after menopause.

OBJECTIVES

To evaluate the association between physical activity and metabolic risk factors at baseline and after 11 years, as well as the change in that association over time in women who were premenopausal and ≥ 40 years at baseline.

METHODS

Subjects in a Norwegian population-based health survey answered questionnaires and had body and serum measurements during 1995-1997 (HUNT 2) and in a follow-up study during 2006-2008 (HUNT 3). Repeated-measures analyses were used to estimate the association between physical activity and metabolic factors, adjusting for age, smoking status, education, alcohol intake, and parity. Adjustment for hormonal treatment and medication was made, as appropriate.

RESULTS

In women remaining premenopausal, a higher physical activity score in HUNT 3 was associated with lower weight (p < 0.01) and waist-hip ratio (p < 0.01) and higher high density lipoprotein (HDL) cholesterol in HUNT 3 (p < 0.01). In women that were postmenopausal by the time of follow-up, a higher physical activity score in HUNT 3 was associated with lower weight (p < 0.01), waist-hip ratio (p < 0.01), triglycerides (p < 0.01), and higher total cholesterol (p < 0.05), HDL cholesterol (p < 0.01), and diastolic blood pressure (p < 0.05) in HUNT 3. The association of total physical activity score with weight and waist-hip ratio was stronger in HUNT 3 than in HUNT 2 (p < 0.01).

CONCLUSION

Increased physical activity may reduce the risk of adverse outcomes and use of pharmacological management in women of menopausal age.

Effects of the menopausal transition on energy expenditure: a MONET Group Study

Objectives

Factors that influence weight gain during the menopausal transition are not fully understood. The purpose of this study was to investigate changes in energy expenditure (EE) across the menopausal transition.

Methods

One hundred and two premenopausal women (age: 49.9 ± 1.9 yrs; BMI: 23.3 ± 2.2 kg/m²) were followed for 5 years. Body composition (DXA), physical activity EE (accelerometer), resting EE and thermic effect of food (indirect calorimetry) were measured annually.

Results

Total EE decreased significantly over time in postmenopausal women (P < 0.05), which was mostly due to a decrease in physical activity EE (P < 0.05). Although average resting EE remained stable over time in postmenopausal women, a significant increase, over the 5-year period, was noted in women who were in the menopausal transition by year 5 (P < 0.05). Finally, the time spent in moderate physical activity decreased and the time spent in sedentary physical activity increased during the menopausal transition (P < 0.05).

Conclusion

These results suggest that menopausal transition is accompanied with a decline in EE mainly characterized by a decrease in physical activity EE and a shift to a more sedentary lifestyle.

Changes in body fat distribution through menopause increase blood pressure independently of total body fat in middle-aged women: the Korean National Health and Nutrition Examination Survey 2007-2010

Blood pressure in women increases sharply in middle age, especially after menopause. As the menopausal transition is known to induce changes in body fat distribution, the aim of this study was to investigate the effect of body fat distribution as compared with the effect of total body fat on blood pressure through the menopausal transition. We analyzed 1422 subjects aged 45-55 years using the database from the Korean National Health and Nutrition Examination Survey 2007-2010. The waist circumference (WC) of post-menopausal women was larger than that of pre-menopausal women (80.44 cm, 95% confidence interval (CI) 79.36-81.52 vs. 78.94 cm, 95% CI 78.27-79.61, P=0.013), but there was no statistically significant difference in body mass index (BMI). Systolic and diastolic blood pressure (SBP and DBP) were significantly higher in post-menopausal women than in pre-menopausal women: SBP was 118.33 mm Hg, 95% CI 116.52-120.15 vs. 115.22 mm Hg, 95% CI 114.17-116.28 (P=0.003) and DBP was 76.94 mm Hg, 95% CI 75.88-77.99 vs. 75.25 mm Hg, 95% CI 74.57-75.93 (P=0.009). BMI and WC were positively correlated with BP. After adjustment for BMI, the correlation of WC with SBP remained significant (β=0.250, 95% CI 0.024-0.476, P=0.030). In a stratified analysis, WC correlated with SBP in women with BMI<25 kg m(-2) (β=0.358, 95% CI 0.138-0.579, P=0.001), but not in women with BMI25 kg m(-2). We conclude that the changes in body fat distribution through the menopausal transition are associated with SBP, independent of total body fat. This finding indicates that alterations in the localization of body fat are another cause of menopause-related changes in BP.

The effect of the menopausal transition on body composition and cardiometabolic risk factors: a Montreal-Ottawa New Emerging Team group study

OBJECTIVE

Cardiovascular disease is the first cause of mortality in women in North America. The risk of cardiovascular disease increases sharply after middle age in women, especially after menopause. The aim was to investigate changes in body composition and cardiometabolic profile throughout the menopausal transition.

METHODS

This was a 5-year observational, longitudinal study on the menopausal transition. The study included 102 premenopausal women at baseline (age, 49.9 ± 1.9 y; body mass index, 23.3 ± 2.2 kg/m). Outcome measures include menopause status, body composition by dual-energy x-ray absorptiometry (total fat mass [FM], trunk FM, and total fat-free mass), waist circumference, visceral and abdominal subcutaneous fat, fasting glucose and insulin levels, homeostasis model assessment of insulin resistance, plasma lipid levels (triglycerides, total cholesterol, and high- and low-density lipoprotein cholesterol), and resting blood pressure.

RESULTS

Repeated-measure analyses revealed significant increases for FM, percentage FM, trunk FM, visceral fat, plasma fasting glucose, and high-density lipoprotein cholesterol (0.05 > P < 0.01) and a significant decrease for plasma glucose levels after follow-up. Those who were in perimenopause or postmenopause by year 3 of the study showed a significant increase in visceral fat (P < 0.01) compared with baseline. Despite some significant changes in the metabolic profile among the menopause statuses, the women did not show any cardiometabolic deterioration by the end of the study.

CONCLUSIONS

Our results suggest that changes in body composition and fat distribution can occur in nonobese women as they go through the menopausal transition. However, these changes were not accompanied by cardiometabolic deteriorations in the present study.

Menopause versus aging: The predictor of obesity and metabolic aberrations among menopausal women of Karnataka, South India

Context:

Increased incidences of cardiovascular disorder and metabolic syndrome particularly after menopause have raised curiosity for the underlying factors. However, it is still a debate whether age or menopausal transition is a greater contributor.

Aims:

To elucidate the inter-relationships of age, menopause, and associated obesity and to assess their independent effects on aggravation of cardio metabolic risk factors in postmenopausal women.

Settings and Design:

Four hundred two women aged between 30 and 75 years were recruited in a cross-sectional study from Southern India. Three hundred sixteen participants exempting exclusion criteria, comprising of 169 premenopausal and 147 postmenopausal women were finally included.

Materials and Methods:

Anthropometric measurements such as weight, height, waist circumference (WC), hip circumference (HC), fat percentage, basal metabolic rate (BMR), and blood pressure were taken. Fasting plasma glucose, postprandial glucose, glycated hemoglobin (HbA1c), lipid profile, and C-reactive protein (CRP) were also measured.

Statistical Analysis Used:

Independent t-test, Analysis of covariates (ANCOVA), Pearson's correlation coefficients and multiple stepwise linear regression model analysis were done.

Results:

A significant increase in physical and metabolic factors was observed in postmenopausal women compared to premenopausal women except WC and HbA1c. Contrastingly, high-density lipoprotein cholesterol (HDL) levels and BMR were significantly decreased. After adjusting for BMI and age, the significant differences in the variables through the menopausal transition persisted, including an increase in WC. Significant correlation was observed between age and measures of general obesity such as BMI (P < 0.05) and fat percentage (P < 0.001) but not with central obesity indices. Menopausal status and WC exerted an independent effect on most of the metabolic risk factors (P < 0.001 or P < 0.01). Fat percentage was the predicting variable for CRP, HbA1c, diastolic blood pressure (P < 0.001), and HDL (P < 0.01). But Age showed independent effect only on HbA1c.

Conclusions:

Menopausal transition brings about anomalies in total body composition characterized by an increased body fat mass and central adiposity. This creates a compatible atmosphere for abnormal metabolism and aggravated cardio metabolic risk factors. Thus, menopausal status and associated obesity is the major predictor of metabolic aberrations over age in menopausal women.

Sex differences in human adipose tissues - the biology of pear shape

Women have more body fat than men, but in contrast to the deleterious metabolic consequences of the central obesity typical of men, the pear-shaped body fat distribution of many women is associated with lower cardiometabolic risk. To understand the mechanisms regulating adiposity and adipose tissue distribution in men and women, significant research attention has focused on comparing adipocyte morphological and metabolic properties, as well as the capacity of preadipocytes derived from different depots for proliferation and differentiation. Available evidence points to possible intrinsic, cell autonomous differences in preadipocytes and adipocytes, as well as modulatory roles for sex steroids, the microenvironment within each adipose tissue, and developmental factors. Gluteal-femoral adipose tissues of women may simply provide a safe lipid reservoir for excess energy, or they may directly regulate systemic metabolism via release of metabolic products or adipokines. We provide a brief overview of the relationship of fat distribution to metabolic health in men and women, and then focus on mechanisms underlying sex differences in adipose tissue biology.

Premature ovarian failure and body composition changes with adjuvant chemotherapy for breast cancer

OBJECTIVE

Premature ovarian failure and weight gain are both common in women receiving adjuvant chemotherapy for breast cancer. The objective of this preliminary analysis was to characterize changes in weight and body composition in premenopausal women receiving adjuvant chemotherapy for early stage breast cancer and investigate whether these changes were associated with chemotherapy-induced ovarian failure (CIOF).

METHODS

The body composition of 43 premenopausal women with stage I or II breast cancer was measured using dual-energy x-ray absorptiometry within 4 weeks before beginning chemotherapy and after 12 months from baseline. At 12 months, the CIOF was determined using the history of amennorhea for 3 months or more and serum follicle-stimulating hormone.

RESULTS

Of the 43 women, 30 (70%) developed CIOF by the 12-month follow-up. Significant weight gain occurred in women with and without CIOF and consisted of fat but not lean mass in the trunk and legs. In women who developed CIOF, truncal fat increased by a median of 1.8 kg (P = 0.0004), whereas truncal lean mass decreased by 0.6 kg (P = 0.02). Women who retained ovarian function gained a median of 0.9 kg (P = 0.06) in truncal fat with no significant change in truncal lean mass. Women with CIOF tended to lose lean mass. Loss of total body lean mass was directly correlated with the decrease in bone density as measured by bone mineral density at the femoral neck (Spearman correlation coefficient, 0.4; P = 0.03). Energy intake decreased similarly in women with and without CIOF (-184 vs -290 kcal, respectively; P = 0.77).

CONCLUSIONS

The results of this small preliminary analysis suggest that body composition changes in women receiving adjuvant chemotherapy for breast cancer include an increase in fat mass in the trunk and leg regions without an increase in fat-free mass. Future research with a larger study cohort and longer follow-up is needed to further investigate the role of CIOF in body composition changes in women with breast cancer. Further research is also needed to evaluate the potential effects of body composition changes on breast cancer outcomes.

Weight change associated with anastrozole and tamoxifen treatment in postmenopausal women with or at high risk of developing breast cancer

Weight gain is commonly reported by breast cancer patients on tamoxifen or aromatase inhibitors. Since weight gain may impact on outcome and compliance we have prospectively assessed the effects of these agents on weight change in three randomised trials for the treatment or prevention of breast cancer. Data on weight change in postmenopausal women from three large clinical trials investigating endocrine therapy for the treatment or prevention of breast cancer were analysed (ATAC, IBIS-I and IBIS-II). In the IBIS-I study, mean weight change on tamoxifen was +0.1 kg (SD 0.1) compared with +0.3 kg (SD 0.1) in women taking the placebo (P = 0.3) between baseline and 12 months of follow-up. In the IBIS-II trial, no statistically significant difference was found between anastrozole and placebo after 12 months of follow-up [+0.8 kg (SD 5.3) vs. +0.5 kg (SD 7.4), P = 0.5]. In the ATAC trial, no statistically significant differences in weight gain between anastrozole and tamoxifen were found after 12 months of follow-up [+1.4 kg (SD 3.9) vs. +1.5 kg (SD 4.0), P = 0.4]. Significant baseline predictors for gaining more than 5 kg of weight after 12 months of follow-up were: being younger than 60 years old, smoking and mastectomy. All three trials demonstrate that weight gain occurs primarily within the first 12 months of active treatment in a subset of patients. In the prevention trials, weight gain does not differ between anastrozole, tamoxifen and placebo and also did not differ between anastrozole and tamoxifen in the treatment trial.

Breastfeeding and subsequent maternal visceral adiposity

Women gain visceral fat during pregnancy. Studies examining the impact of breastfeeding on maternal body composition are inconclusive. We examined the extent to which breastfeeding was associated with visceral adiposity in a sample of US women. This was a cross-sectional analysis of 351 women aged 45-58 years, who were free of clinical cardiovascular disease and had not used oral contraceptives or hormone replacement therapy in the 3 months prior to enrollment in the Study of Women's Health Across the Nation (SWAN)-Heart Study (2001-2003). History of breastfeeding was self-reported. Computed tomography was used to assess abdominal adiposity. Among premenopausal/early-peri-menopausal mothers, those who never breastfed had 28% greater visceral adiposity (95% confidence interval (CI): 11-49, P = 0.001), 4.7% greater waist-hip ratio (95% CI: 1.9-7.4, P < 0.001), and 6.49 cm greater waist circumference (95% CI: 3.71-9.26, P < 0.001) than mothers who breastfed all of their children for ≥3 months in models adjusting for study site; age; parity; years since last birth; socioeconomic, lifestyle, and family history variables; early adult BMI; and current BMI. In comparison to women who were nulliparous, mothers who breastfed all of their children for ≥3 months had similar amounts of visceral fat (P > 0.05). In contrast, premenopausal/early-peri-menopausal mothers who had never breastfed had significantly greater visceral adiposity (42% (95% CI: 17-70), P < 0.001), waist circumference (6.15 cm (95% CI: 2.75-9.56), P < 0.001), and waist-hip ratio (3.7% (95% CI: 0.69-6.8), P = 0.02) than nulliparous women. No significant relationships were observed among late peri-menopausal/postmenopausal women. In conclusion, until menopause, mothers who did not breastfeed all of their children for ≥3 months exhibit significantly greater amounts of metabolically active visceral fat than mothers who had breastfed all of their children for ≥3 months.